Method and apparatus for manipulating stretchable sheet material



Sept. 3, 1935. F. D. FOWLER 2,013,344

METHOD AND APPARATUS FOR MANIPULATING STRETCHABLE SHEET MATERIAL FiledJune 8, 1934 Patented Sept. 3, 1935 warren STATES METHOD AND APPARATUSFOR MANIPU- LATING STRETCHABLE SHEET MATERIAL Fred D. Fowler, Newton,Mass., assignorto Hood Rubber Company, Inc., Watertown, corporation ofDelaware Mass., at

Application June 8, 1934, Serial No. 729,723

16 Claims.

This invention relates to the manipulation of stretchable and tackysheet material, such for example as the rubberized stcckinette used inthe manufacture of rubber footwear.

In unrceling such material from the rolled form in which it is handled,difiiculty has been encountered in pulling the easily stretched materialto break its adhesion with the next underlying convolution withoutdistorting it obiectionably or stretching it to an undesirable degree.In the distorted and stretched condition it is difficult to cut andmaintain it in the desired shapes, and its stretchability in use isobjectionably lessened.

The chief objects of the invention are to provide for drawing thematerial from its roll without objectionable distortion of it, and toprovide for restoring to the material the stretchability that it mayhave lost by virtue of the drawing force.

These and further-objects will be apparent from the followingdescription, reference being had to the accompanying drawing, in which:

Fig. l is a vertical section of apparatus constructed according to andembodying the invention in its preferred form.

Fig. 2 is a perspective view, with parts broken away, of a sheet ofstretchable material to be manipulated.

The stretchable sheet material chosen for illustrationconsists of alayer IU of highly stretchable stockinette having a surface coating llof tacky rubber. After the rubberizing procedure this material isordinarily handled in the form of a roll !2, of which the convolutionsare ordinarily disposed with their fabric face outward.

The tacky rubber face causes adhesion of the convolutions and somepulling force is required to separate them.

For un-rolling the material, apparatus is provided comprising a framesupport l4 formed with slots 83 in which the arbor of the roll I2 isguided as shown. Below the roll are journaled a pair of pulleys l5 and16 having mounted upon them a belt I! which has an outer face-of cardcloth I8. As the tips of the card teeth are disposed radially outwardfrom the neutral axis of the belt, these teeth accelerate in linearspeed through a short range and spread apart as their course is changedby the pulley, and these tips decelerate and move closer together againwhen the belt passes from the pulley into its straight reach.

The pulleys l5 and I6 are mounted in suchrelation to the roll I2 thatthe card teeth of the upper reach of the belt, moving in the directionof the arrow, engage the sheet material at the bottom of the rollsomewhat before the direction of these teeth is changed by the pulleyl5.

Preferably the roll I2 is so guided that it rests upon the card teethand its weight assists in engaging the teeth in the cloth. The arborguiding slots l3 are directed toward the axis of the pulley 15 as shownso that as the roll becomes smaller it will continue to maintain itsproper relation to the card teeth.

After the material is drawn from the roll, it remains in engagement withthe card teeth until somewhat after the belt passes from the pulley l5into its lower reach. It is then drawn downwardly from the card teethand is guided by a pair of rollers l9 and 20 onto a conveyor belt 2!which passes over a pulley 22, all mounted in the frame support. Theseveral pulleys and roll ers may be driven by any suitable means, forexample by the sprocket chain drives shown connected with a suitablesource of power (not shown).

In operation, the parts being driven in the direction of the arrows, thematerial is progressively drawn from the roll l2 and fed onto theconveyor 2| to be carried to cutting or other operating stations formaking the desired articles.

Owing to the fact that the card teeth l8 engage the stockinette somewhatbefore the belt starts its passage upon the pulley l5 the material iswell engaged by the teeth before the latter are accelerated and movedapart by the curving of the belt upon the pulley. The arrangement issuch that the card teeth start their accelera tion just as or preferablyslightly before the line of separation of the material from the roll isreached, so that the slight stretching of the material occurs at theline of separation to overcome most effectively the adhesion of thematerial and the frictional resistance of the roll mounting. I V

As the card teeth are continually in simultaneous engagementwith bothstripped and unstripped portions of the sheet material at the two sidesof the line of separation, the operation is entirely controlled, and thestripping is effected without objectionable jerking and with theimparting of a small determinate degree of stretch to the material. Thedegree of stretch is always the same, being determined by the amount ofseparating movement of the card teeth with relation to each other asthey pass onto the pulley.

Inasmuch as the card teeth are not disengaged from the fabric untilafter they have passed from the pulley into the straight lower reach ofthe belt, and have thereby been decelerated and moved to their closerrelationship again, they exert during such deceleration a progressivecompacting force on the sheet longitudinally thereof which restores thematerial substantially to its initial unstretched condition. The pulleysl9 and 20 are rotated at peripheral speeds' equal to the linear speed ofthe conveyor belt 2| sothat the sheet material is fed onto the conveyorwith substantially no loss of stretchability.

I claim:

1. The method of unrolling stretchable sheet material from a rollthereof which comprises contacting the surface of the rolled material inmovement compelling relation thereto and advancing the contactedmaterial past the line of separation of it from the roll to unroll itwhile accelerating the contacted portion of the mate rial to impart astretching force to it at the line of separation.

2. The method of removing tacky stretchable sheet material from a rollthereof which comprises engaging the sheet material simultaneously alongthe two sides of the line of separation of the material from its rolland advancing the engaged portions in the direction to unroll the sheetwhile moving the engaged portions further apart to impart a stretchingforce to the material at the line of separation.

3-. A method as defined in claim 2 in which the engaged portions of theunrolled material are subsequently moved closer together to impart acompacting force to the material.

4. A method as defined in claim 2 in which the engaged portions aremoved further apart by accelerating the leading engaged portion withrelation to the following engaged portion for a determinately limitedextent to impart a determinately limited amount of stretch to thematerial.

5. A method as defined in claim 2 in which the engaged portions aremoved further apart by accelerating the leading engaged portion withrelation to the following engaged portion for a determinately limitedextent to impart a determinately limited amount of stretch to thematerial and the leading engaged portion is subsequently deceleratedwith relation to the following engaged portion to compact the materialthe amount it was stretched.

6. The method of removing tacky stretchable sheet material from a rollthereof which comprises engaging the surface of the rolled material witha plurality of engaging elements at positions along the length of thesheet, and advancing the elements past the line of separation of thematerial from the roll while moving the elements further apart to imparta stretching force to the material at the line of separation.

7. A method as defined in claim 6 in which the elements are movedfurther apart by moving them from a straight path into a path about anaxis to accelerate the leading elements with relation to the followingelements.

8. A method as defined in claim 6 in which the stretched material issubsequently compacted by moving the said elements from a path about anaxis into a straight path, thereby decelerating leading elements withrelation to the following elements.

9. The method of removing stretchable sheet material from a roll thereofwhich comprises engaging the material with a plurality of engagingelements at positions along the length of the sheet. advancing saidelements in the direction to unroll the material and subsequently movingthe elements closer together to compact the unrolled materiallongitudinally.

10. A method as defined in claim 9- in which 1 the elements are movedcloser together by moving them from a path about an axis into a straightplurality of engaging elements, and means for moving said elements intoengagement with the rolled material at positions along the length of thesheet and for advancing the elements in the direction to unroll thematerial, the said means including means for moving the elements furtherapart at the line of separation of the material from the roll to imparta stretching force to the material at the line of separation.

13. Apparatus for unrolling tacky stretchable sheet material from a rollthereof comprising a plurality of engaging elements, and means formoving said elements into engagement with the material at positionsalong the length of the sheet and for advancing the elements in thedirection to unroll the material, the said means including means formoving the elements closer together lengthwise of the unrolled sheet toimpart a compacting force thereto.

14. Apparatus for unrolling tacky stretchable sheet material from a rollthereof comprising means including a pulley and a belt passing thereoverhaving a surface of card cloth for engaging the rolled material and foradvancing the same to unroll it, and means for maintaining the roll atsuch a position in relation to the point at which the belt begins itscurvature upon the pulley that the acceleration of the card teeth,occurring when the belt passes onto the pulley, imparts a stretchingforce to the material at the line of separation of the material from theroll.

15. Apparatus as defined in claim 14 comprising means for disengagingthe material from the card teeth after the belt passes its point ofdeparture from the pulley, whereby the deceleration occurring at suchpoint imparts a longitudinal compacting force to the material.

16. Apparatus for manipulating stretchable sheet material comprisingmeans including a pulley and a belt passing thereover, said belt hav inga movement-compelling face comprising card cloth for contacting thematerial and advancing it past the point of departure of the belt fromthe pulley, whereby the deceleration of the materialcontacting portionsof the belt face occurring at such point imparts a longitudinalcompacting force to the material.

FRED D. FOWLER.

